Since systemd is consistently using /dev/urandom before it is
initialized, we can't see the other potentially dangerous users of
/dev/urandom immediately after boot.  So print the first ten such
complaints instead.

Cc: sta...@kernel.org
Signed-off-by: Theodore Ts'o <ty...@mit.edu>
---
 drivers/char/random.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 4e2627a..74596d3 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1458,12 +1458,16 @@ random_read(struct file *file, char __user *buf, size_t 
nbytes, loff_t *ppos)
 static ssize_t
 urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
 {
+       static int maxwarn = 10;
        int ret;
 
-       if (unlikely(nonblocking_pool.initialized == 0))
-               printk_once(KERN_NOTICE "random: %s urandom read "
-                           "with %d bits of entropy available\n",
-                           current->comm, nonblocking_pool.entropy_total);
+       if (unlikely(nonblocking_pool.initialized == 0) &&
+           maxwarn > 0) {
+               maxwarn--;
+               printk(KERN_NOTICE "random: %s: uninitialized urandom read "
+                      "(%d bytes read, %d bits of entropy available)\n",
+                      current->comm, nbytes, nonblocking_pool.entropy_total);
+       }
 
        nbytes = min_t(size_t, nbytes, INT_MAX >> (ENTROPY_SHIFT + 3));
        ret = extract_entropy_user(&nonblocking_pool, buf, nbytes);
-- 
2.5.0

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